| 摘要 |
PROBLEM TO BE SOLVED: To interrupt optical transmission by detecting a broken optical transmission line in 2-way transmission using an optical amplifier in the optical 2-way transmitter amplifying an optical signal to make 2-way communication through the optical transmission line. SOLUTION: A 1st optical directional coupler(ODC) 31 synthesizes a transmission signal from a signal light transmission section 22 and a stimulated light from a stimulated light source 32 whose wavelength differs from that of other station and gives the synthesized light to an input side of an optical amplifier section 34, a 2nd ODC 36 provides an output the light to a transmitter side, or a received light is branched to a signal reception section 23 or a 2nd band pass filter(BPF) of a control means. When a stimulated light of the same wavelength as a stimulated light of its own station is included in a received light by the 2nd BPS 39 as the reflected light, the light is received by a stimulated light reception section 40 and a stimulated light source control section 41 controls the stimulated light source 32 to stop its outputvdepending on this reception. |
